In recent years, so-called single use or disposable cameras have become popular. Such cameras include an internal frame for supporting conventional camera components, plus a film cartridge and a spool located on opposite sides of an exposure gate for the camera. Prior to use, the unexposed film is wound from the cartridge onto the spool. During use, each exposed frame is wound back into the cartridge. When all of the film has been exposed, the camera is taken to a photographic processor, where the camera housing is opened and the cartridge is removed. The remainder of the camera is then returned to the manufacturer for recovery of reusable components.
FIG. 1 shows an exploded view of a camera housing 10 used for some types of single use cameras. Housing 10 is disclosed in copending, commonly assigned U.S. application Ser. No. 08/327,250 filed Oct. 21, 1994 by James D. Boyd, the contents of which are incorporated by reference into this application. Housing 10 comprises a front cover part 12 and a back cover part 14 which in an assembled camera enclose an internal camera frame on which the functional components of the camera are mounted, not illustrated. Thus, cover pan 12 includes an opening 16 for a taking lens, an opening 18 for a viewfinder, an opening 20 for a flash unit, and an integral flash activation button 22. A more compact camera also is made without the flash unit and flash activation button. When the cover parts are assembled about the internal camera components, mating partial openings 24.sub.f and 24.sub.b cooperate to provide an opening for a shutter trigger button; and mating partial openings 26.sub.f and 26.sub.b cooperate to provide an opening for a window to view a frame counterwheel. In an assembled camera, a trio of positioning pins 28, 30, 32 extended from back cover part 14 mate with a corresponding set of bores, not illustrated, in front cover part 12.
As seen in FIG. 1, front cover part 12 includes a top wall 34, a bottom wall 36, a left end wall 38, and a fight end wall 40. Similarly, back cover part 14 includes a top wall 42, a bottom wall 44, a left end wall 46, and a fight end wall 48. In the illustrated camera housing, cooperating fastener pairs are included between the respective top, bottom and end walls, to securely join the front and back cover parts and thereby prevent inadvertent opening of the camera and exposure of film. However, those skilled in the art will appreciate that, for suitably rigid front and back cover parts, cooperating fastener pairs could be provided only between the respective end walls, which typically are opened by the photographic processor.
First and second cooperating fastener pairs extend, respectively, between top walls 34, 42 and bottom walls 36, 44. An essentially rectangular opening 50 is provided through top wall 42 and a similar opening 52 is provided through bottom wall 44. Flexible fastener hooks 54, 56 extend into openings 50, 52, respectively. In an outer surface of top wall 42, a recess 58 is formed behind fastener hook 54. An essentially identical recess, not illustrated, is formed in an outside surface of bottom wall 44 behind fastener hook 56. Opposite opening 50 and hook 54 and opposite opening 52 and hook 56, top wall 34 and bottom wall 36 support, respectively, a pair of flexible catch tabs 60, 62, the latter being fragmentarily visible through opening 16. Each of catch tabs 60, 62 includes an opening 64 for receiving one of hooks 54, 56 when the cover parts are assembled. Each of catch tabs 60, 62 also includes an outwardly extended lip 66 which fits into recess 58 when the cover parts are assembled. An elongated recess 68 is formed in each of top wall 34 and bottom wall 36 in front of opening 64. Alternatively, the fastener hooks could be on front cover part 12 and the catch tabs could be on rear cover part 14.
Third and fourth cooperating fastener pairs extend, respectively, between left end walls 38, 46 and right end walls 40, 48. Each of end walls 38, 40 includes a recess 70 in which a pair of vertically spaced catches 72, 74 are located. Opposite recesses 70, end walls 46, 48 support, respectively, a pair of flexible catch tabs 75, 76. Each of the catch tabs includes a pair of vertically spaced openings 77, 78 for receiving catches 72, 74 when the cover parts are assembled. Catch tabs 75, 76 also include respective tapered lips 80, 82 which extend into recesses 70 when the cover parts are assembled. Alternatively, the catches could be on back cover part 14 and the catch tabs could be on front cover part 12.
To assemble a camera using cover parts 12, 14, the internal components of the camera, not illustrated, are assembled and captured between front and back cover parts 12, 14. As the cover parts are brought together, positioning pins 28, 30, 32 enter the bores in cover part 12 to pilot the cover parts into proper mating engagement. As the pins enter their associated bores, fastener hooks 54, 56 flex to ride under catch tabs 60, 62 and eventually the hooks snap outward into engagement with openings 64. Preferably, fastener hooks 54, 56 then are ultrasonically or thermally welded to catch tabs 60, 62, to provide further assurance that the consumer will not be able to open the camera. Or the tips of the hooks may be omitted and the arms of the hooks welded to the catch tabs. In either event, the resultant, welded fastener pairs can be released by inserting a cuffing tool between recess 58 and lip 66 to cut the welded bond between the two, or by inserting a cutting tool along recess 68 to engage and cut the welded bond.
Essentially simultaneously with engagement of fastener hooks 54, 56 and catch tabs 60, 62, catch tabs 75, 76 flex to ride over catches 72, 74 and eventually the catch tabs snap inward over the catches. However, catch tabs 75, 76 and catches 72, 74 are left in mechanical engagement, rather than being welded, to facilitate their being opened by a photographic processor after all the film has been exposed. These fastener pairs can be opened by inserting a prying tool between lips 80, 82 and recess 70 to flex catch tabs 75, 76 out of engagement with catches 72, 74. Though this feature is not illustrated, the fight and left ends of back cover part 14 can then be pivoted away from the back of the camera about lines of weakness in a back wall of the back cover part, not illustrated, to permit removal of the enclosed film cartridge and a battery for the flash unit. Commonly, the processor will then re-engage the fastener pairs 72, 74; 75, 76 and return the camera to its manufacturer for removal of reusable internal components.
A need thus has developed for a simple, reliable method and apparatus for a manufacturer of such a camera to use to completely open the camera by removing the front and back cover pans to provide total access to the camera's internal components. Such method and apparatus could be used to open a used camera for removal of internal components or to open a new camera to repair defects discovered after initial assembly.